Manufacture of azophthalein dyestuffs



Patented Nov. 15, 1932 UNITED STATES PATENT OFFICE Km EIm-or BASEL, swrrznanmn, ASSIGNOR To run rum J. money-sat,

or BASEL, SWITZERLAND I MANUFACTURE OF AZOPHTHALEIN DYESTUFFS 7 No Drawing. Application filed May 17, 1929, Serial Ko.l364,002,' and inGermany May 24, 1928. i

By condensing alkylated amino-hydroxybenzoyl-benzoic acids with resorcinol or derivaties thereof, such as sulphonic acids or carboxylic acids of resorcinol, phthalein dye- 5 stufls have been made which in general dye red tints in part with aid of a mordant.

This. invention relates to the manufacture of new dyestufi's of this series also containing theresorcinol residue by condensing an 10 amino-hydroxy benzoyl benzoic acid alkylated Tor arylated at the nitrogen, in equimolecu- .larproportions with an azo-dyestufl which contains .resorcinol or a derivative thereof, such that there is still a free para-position 1 relative to one of the hydroxyl-groups thereof. I j

In the lactone form these dyestuffs maybe supposed to have thejgeneral formula in which" R=alkyl, R =alkyl or H and Ar=anyaromatic residue. 1

" While the condensation products from simple resorcinol monoazo-dyestufis are of themselves of little value as dyestufls, they find technical application as intermediate 35 products." On the other hand, the azo- 7 phthaleins obtained by means of az'o-dyestufis from resorcinol and ortho-hydroxyamino-compounds exhibit surprising new effects. These dyestuffs are genuine mordant aodyestufis which, when after-treated on the fibre with metal salts, yield fast valuable dyeings and, indeed, what is not'to be expected, these are of blue to greenish-blue tints.

Other mordant dyeing groups may be contained in the resorcinol nionoazodyestufis such as carboxyl groups or one or more carboxyl groups with a hydroxyl group in ortho position. In the latter case the after-chromed dyeings are of reddish to brown-red tints.

'-The condensation'process 'm'ayconsist in heating the components with sulphuric acid 66 B, or with strongly concentrated sulphuric acid for some hours. 1 i

The following examples illustrate the in- For working up the product the mass is poured into water, filtered and the dyestufli acid is washed neutral anddried. It is a powder of'bronze lustre which dissolves in concentrated sulphuric acid to a yellowishred solution and in sodium carbonate to'a 6,3 parts of diethylaminohydroxybenzoylv benzoic acid and 7,8 kilos of the monoazodyestuff from 1 2 4-aminonaphtholsulphonic acid and resorcinol are mixed together 1 and introduced at 2030 G. into 7 0 kilos of concentrated sulphuric acid. The whole is heated to709', C. and, kept at, this tempera? ture for 4-5 hours. The reaction takes place according to the following formula:

on on a I 7 0:11am OH R COOH Themass is then worked up as described in Examplel.

The dyestufi' is a blue powder of strong bronze lustre, soluble in concentrated..sulphuric acid toa green solution and in sodium carbonate to a pure blue solution; it dyes wool in an acid bath pure greenish-blue of moderate fastness; by, after-chroming or after-coppering the tint becomes more dull but the fastness is enhanced. If instead of the resorcinolmonoazo-dyestutf named above,

in this example there is used the analogous dyestuff from nitro-1z2z4 aminonaphtholsulphonic acid and resorcinol, there is obtained a dyestufi which yields green tints when after chromed on wool. Its solution in concentrated sulphuric acid is brownish-red and that in sodium carbonate-is blue-green.

Ewample 3 5,8 kilos of dimethylamino-hydroxybenzoyl-benzoic acid are condensed with 5,2 kilos of concentratedsulphuric acid at 7 0C. for

' 24 hours. The product is worked up as described in Example 1, whereby there are obtained 10 kilos of the azo-phthalein dyestufi'. The reaction takes place according to the following formula:

on on 015mm OH COOH m 0 i (I..

It dissolves in concentrated'sulphuric acid to. a brown-red solution, in sodium carbonate to a red solution.-- When after-chromed" on WOOl it yields beautiful brown-red tints.

The condensation products from benzoylbenzoic acids and the monoazo-dyestuffs from resorcinol and cleri'vatives thereof with aniline and its sulphoniclacids, such as sulpha- 'nilic acid,'amino salicyclic'acid, chloraniline- "sulphonic acid or with naphthylamine or its 'sulphonicacids, such' as 1 5- or 2:6-naph- 'thylaminesulphonic acid, are orange, brown to red dyestuffs.

\ They are of little interest from the pointof view of the dyer but find use as intermediate products for making dyestuffs.

In these examples, instead of resorcin, there can also be used'cresorcin (l-methyl-Qz l-dioxybenzene) and other resorcinol derivatives.

What I claim is 1. A manufacture of azophthalein dyestuffs, consisting in condensing an aminohydroxybenzoylbenzoic- 'acid, alkylated at the nitrogen, in equimolecular proportions with a resorcinolic monoa'zo-dyestuff having a free para-position to one of the'hydroxylgroups of the resorcinol radical. i g

V 2; A manufacture of azophthalein dyestulfs, consisting in condensing a dialkylami- .nohydroxybenzoylbenzoic acid in equimolecular proportions with a monoazodyestufli' from resorcinol having afree para-position to one of the hydroxyl groups of the resor- V c-inolradical. Y

3. A manufacture of azophthalein dyestuffs, consisting in condensing a diethylaminohydroxybenzoylbenzoic acid in, equimolecular proportions with a monoazo-dyestufi from resorcinol having a free para-position to one of the hydroxyl groups of the resorcinol radical. o r

.4. As new products of manufacture, the hereinbefore described azophthalein dyestufis having in the lactone form probably the following formula:

hanced fastness.

In witness whereof I have hereunto signed my name this 4th day of May, 1929.

ADOLF KREBSER; 

